\begin{tikzpicture}
    \tkzDefPoints{0/0/B, 4/0/C, 1/2/A}
    \tkzDefMidPoint(B,C)  \tkzGetPoint{D}

    \tkzDrawPolygon(A,B,C)
    \tkzDrawSegment(A,D)
    \tkzLabelPoints[above](A)
    \tkzLabelPoints[below](B,C,D)

    % 角 BAD > 角 DAC
    % \tkzFindAngle(B,A,D) \tkzGetAngle{an} \tkzLabelAngle(B,A,D){$\pgfmathprintnumber{\an}$}
    % \tkzFindAngle(D,A,C) \tkzGetAngle{an} \tkzLabelAngle[pos=0.5](D,A,C){$\pgfmathprintnumber{\an}$}
\end{tikzpicture}

